A birthchart, natal chart or horoscope is a map of the planets and their locations within the zodiac at the date, time and place of birth. Its interpretation is basically a psychological analysis of a person's character and can show potential for further development. However, nothing is cast in stone - there is always free will.

A horoscope, the name taken the Greek "hora" meaning an hour or of the hour, is built up of many layers. From the basic calculation of a chart or horoscope the houses are formed. Each of those houses will be in one or more of the twelve zodiac signs. Each zodiac sign is part of a triplicity or quadruplicity, otherwise known as the elements and qualities. These form the basis for psychological analysis of the character, the foundations from which to build the layers on to complete the picture.

The starting point of a chart or horoscope is the Ascendant (ASC), the sign which was rising on the Eastern horizon at the time of birth. This is also the cusp of the first house and all subsequent houses follow round the chart anti-clockwise. The sign that was rising in this instance is Leo and all subsequent signs follow round the chart anti-clockwise.

Each segment of the outer circle is the extent of each sign represented by a glyph. Each segment being 30 degrees, starting at 0 degrees and ending at 29 degrees, again going anti-clockwise.

Each segment of the inner circle is the extent of each house. The size of the house can vary in degrees according to which house system is used. Some houses can span over several signs. Where a house spans at least three signs, the sign or signs, which do not form a cusp, are known as INTERCEPTED signs.

Each dividing line between the houses is known as the cusp of the following house. As in the Ascendant line being the cusp of the first house, so the next line is the cusp of the second house and so on anti-clockwise.

The cusp of the fourth house is also the Imum Coeli (IC) which is the lowest point of the chart. It symbolises our roots.

The cusp of the seventh house is also the Descendant (DSC). This is the point and sign that was setting at the time of birth.

The cusp of the tenth house is also the Midheaven or Medium Coeli (MC). This is the highest point of the chart. It symbolises what we identify with.

Within each of the houses are the planets, represented by their glyphs. Some other points are often included, such as asteroids and the Arabian Part of Fortune.

The coloured lines going across the chart are the aspects between the planets. Each colour represents a different aspect.